Smart railway transportation systems aim to make the trains operate in a more intelligent and flexible manner. Reliable train‐to‐train communication, which can increase the efficiency and safety of the train operation, is getting more concern in recent researches, and different communication solutions can be applied to carry out the data communication. However, its propagation and safety analysis is not systematically put forward. In this work, the structure and working principle of a train‐to‐train communication system are proposed. In order to have a better performance, multi‐communication channels are involved. Three different modems are applied to make sure that the system can implement the communication task in different situations. What is more, the long‐range communication modem provides not only long distance communication but also distance measurement between two trains. The propagation analysis based on different carrier waves and application scenarios is discussed. The system safety is evaluated by means of Petri nets, and the analysis procedure can be reused for analysing different system structures.